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61.
The one-way information communication provision does not impress listeners well. As an efficient way, Question & Answer can not only help listeners to comprehend the content of information but also help information providers understand the response of listeners. However, it is not easy for everyone to create suitable questions. In this paper, we propose an automatic quiz generation system using tourism blogs. The system can generate quizzes by extracting feature words of the topic keyword from blogs. Our purpose is to help tourism information providers to advertise their tourism events in an interactive way, in order to impress tourists. When compared with other methods of quiz generation, we demonstrate that our method is more suitable for information communication provision.  相似文献   
62.
Gas chromatographic distillation (GCD) based ors ASTM 02887 has been applied to characterizing the boiling range distribution of upgraded coal-derived liquids. It has beer demonstrated that the GCD method based on ASTM D2887 can be used as a substitute for ASTM D2892. A variety of coal-derived liquids can be characterized and the procedure may be effective for estimating the degree of conversion as a means of screening for hydroconversion catalysts.  相似文献   
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Crosslinked structures of the permanent set wool fiber treated with boiling water at a 40% extension state and the control fiber were studied by analyzing the rubberlike force-extension curve of the swollen fiber in a mixed solution composed of equal volumes of 8M LiBr and butyl carbitol. The thiol and disulfide contents of set fibers were also determined. It was found that (1) the disulfide (SS) bonds in low-sulfur (LS) microfibril protein transform into new crosslinkages in boiling water, but the SS bonds in high-sulfur matrix protein remain intact, (2) the SS bonds in α-helical segments becomes reactive only at the extension state of fiber and produces a free thiol group, and (3) intramolecular SS bonds may exist in the α-helical segments. Discussion was also made about the closeness of the number of crosslinkage sites of SS bonds obtained from the present rubber elasticity theory and from the theoretical analysis of the amino acid sequence of the intermediate filament. The cross-linking structure model in LS protein was proposed. It was suggested further that the setting mechanism for new crosslinkage theory seems to be unsatisfactory, since the new crosslinkages do not contribute to stabilize the extended conformation of the wool chain. © 1996 John Wiley & Sons, Inc.  相似文献   
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ABSTRACT

The applicability of various zeolite catalysts and commercial HDS catalysts to the secondary hydrotreatment of coal-derived liquids was examined in relation to the chemical structure of upgraded liquids. The catalytic activities of zeolite catalysts for HI conversion is lower than are the activities of Ni-Mo, Ni-Co-Mo, Co-Mo and Ni-W catalysts. However, as regards hydrogenation and the removal of nitrogen, zeolite catalysts such as natural clinoptilolite and mordenite have almost the same activity as do Co-Mo and Ni-W catalysts. As to the removal of oxygen, it was proved that zeolite catalysts had a functionality to remove oxygen as COx gas, and HDS catalysts had a high activity for hydrodeoxygenation.  相似文献   
68.
ABSTRACT

Gas chromatographic distillation (GCD) based ors ASTM 02887 has been applied to characterizing the boiling range distribution of upgraded coal-derived liquids. It has beer demonstrated that the GCD method based on ASTM D2887 can be used as a substitute for ASTM D2892. A variety of coal-derived liquids can be characterized and the procedure may be effective for estimating the degree of conversion as a means of screening for hydroconversion catalysts.  相似文献   
69.
An extracellular endo-1,4-beta-xylanase was purified from the culture filtrate of a filamentous fungus, Penicillium citrinum strain FERM P-15944, grown on birch-wood xylan. The purified enzyme showed a single band on SDS-PAGE with an apparent M(r) of 31.6 kDa. The xylanase activity was optimal at pH 6.0 and 50 degrees C. Southern blot analysis indicated that the xylanase gene (xynB) was present as a single copy in the genome. The genomic DNA and cDNAs encoding this protein were cloned and sequenced. An open reading frame of xynB was interrupted by nine introns and encoded a presumed prepropeptide of 25 amino acids and a mature protein of 302 amino acids. Sequence alignment and the constructed neighbor-joining tree showed that the P. citrinum enzyme belongs to glycoside hydrolase family 10 and is closely related to several other xylanases from penicillia and black aspergilli. The xynB cDNA was functionally expressed in the methylotrophic yeast Pichia pastoris.  相似文献   
70.
The applicability of various zeolite catalysts and commercial HDS catalysts to the secondary hydrotreatment of coal-derived liquids was examined in relation to the chemical structure of upgraded liquids. The catalytic activities of zeolite catalysts for HI conversion is lower than are the activities of Ni-Mo, Ni-Co-Mo, Co-Mo and Ni-W catalysts. However, as regards hydrogenation and the removal of nitrogen, zeolite catalysts such as natural clinoptilolite and mordenite have almost the same activity as do Co-Mo and Ni-W catalysts. As to the removal of oxygen, it was proved that zeolite catalysts had a functionality to remove oxygen as COx gas, and HDS catalysts had a high activity for hydrodeoxygenation.  相似文献   
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